class_docstr: Swap-in HDF5 File Handler.
code: def _get_selection_data(self, num_rows, num_cols):
      selection = {
          "wvc_selection": xr.DataArray(
              da.ones((num_rows, num_cols), chunks=1024, dtype=np.int8),
              attrs={
                  "fill_value": 0,
                  "scale_factor": 1.0,
                  "add_offset": 0.0,
                  "units": "count",
                  "valid range": [1, 8],
              },
              dims=("y", "x"),
          ),
          "wind_speed_selection": xr.DataArray(
              da.ones(
                  (num_rows, num_cols), chunks=1024, dtype=np.int16
              ),
              attrs={
                  "fill_value": -32767,
                  "scale_factor": 0.1,
                  "add_offset": 0.0,
                  "units": "deg",
                  "valid range": [0, 3599],
              },
              dims=("y", "x"),
          ),
          "wind_dir_selection": xr.DataArray(
              da.ones(
                  (num_rows, num_cols), chunks=1024, dtype=np.int16
              ),
              attrs={
                  "fill_value": -32767,
                  "scale_factor": 0.01,
                  "add_offset": 0.0,
                  "units": "m/s",
                  "valid range": [0, 5000],
              },
              dims=("y", "x"),
          ),
          "model_dir": xr.DataArray(
              da.ones(
                  (num_rows, num_cols), chunks=1024, dtype=np.int16
              ),
              attrs={
                  "fill_value": -32767,
                  "scale_factor": 0.01,
                  "add_offset": 0.0,
                  "units": "m/s",
                  "valid range": [0, 5000],
              },
              dims=("y", "x"),
          ),
          "model_speed": xr.DataArray(
              da.ones(
                  (num_rows, num_cols), chunks=1024, dtype=np.int16
              ),
              attrs={
                  "fill_value": -32767,
                  "scale_factor": 0.1,
                  "add_offset": 0.0,
                  "units": "deg",
                  "valid range": [0, 3599],
              },
              dims=("y", "x"),
          ),
          "num_ambigs": xr.DataArray(
              da.ones((num_rows, num_cols), chunks=1024, dtype=np.int8),
              attrs={
                  "fill_value": 0,
                  "scale_factor": 1.0,
                  "add_offset": 0.0,
                  "units": "count",
                  "valid range": [1, 8],
              },
              dims=("y", "x"),
          ),
          "num_in_aft": xr.DataArray(
              da.ones((num_rows, num_cols), chunks=1024, dtype=np.int8),
              attrs={
                  "fill_value": 0,
                  "scale_factor": 1.0,
                  "add_offset": 0.0,
                  "units": "count",
                  "valid range": [1, 127],
              },
              dims=("y", "x"),
          ),
          "num_in_fore": xr.DataArray(
              da.ones((num_rows, num_cols), chunks=1024, dtype=np.int8),
              attrs={
                  "fill_value": 0,
                  "scale_factor": 1.0,
                  "add_offset": 0.0,
                  "units": "count",
                  "valid range": [1, 127],
              },
              dims=("y", "x"),
          ),
          "num_out_aft": xr.DataArray(
              da.ones((num_rows, num_cols), chunks=1024, dtype=np.int8),
              attrs={
                  "fill_value": 0,
                  "scale_factor": 1.0,
                  "add_offset": 0.0,
                  "units": "count",
                  "valid range": [1, 127],
              },
              dims=("y", "x"),
          ),
          "num_out_fore": xr.DataArray(
              da.ones((num_rows, num_cols), chunks=1024, dtype=np.int8),
              attrs={
                  "fill_value": 0,
                  "scale_factor": 1.0,
                  "add_offset": 0.0,
                  "units": "count",
                  "valid range": [1, 127],
              },
              dims=("y", "x"),
          ),
          "wvc_quality_flag": xr.DataArray(
              da.ones(
                  (num_rows, num_cols), chunks=1024, dtype=np.uint16
              ),
              attrs={
                  "fill_value": 2.14748e09,
                  "scale_factor": 1.0,
                  "add_offset": 0.0,
                  "units": "na",
                  "valid range": [1, 2.14748e09],
              },
              dims=("y", "x"),
          ),
      }
      return selection
  
imports: import os
  import unittest
  from unittest import mock
  import dask.array
  import numpy
  import pytest
  import xarray
  from satpy.tests.reader_tests.test_hdf5_utils import FakeHDF5FileHandler
label_desc: Use image node_id 4 for calling the FakeHDF5FileHandler2 obj's underlying member method code with example usage: obj._get_selection_data(num_rows, num_cols) and returns: selection